Internal-combustion engine



Nov. 20, 1951 G. J. LUGT 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 7 SheetsSheet 2 Nov. 20,1951 LUGT 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 '7 Sheens-Sheet 3 FIGQNov. 20, 1951 J. LUGT INTERNAL-COMBUSTION ENGINE '7 Sheets-Sheet 4 FiledSept. 17, 1947 M a? j I m l /J w u mu 4. m Z F m Nov, 20, 1951 I J LUGT2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 1'7, 1947 '7 Sheets-Sheet 5 NOV.20, 1951 I G 2,575,633

INTERNAL-COMBUSTION ENGINE Filed Sept. 17, 1947 1 '7 Sheets-Sheet 6 TF'W Nov. 20, 1951 7 Sheets-Sheet 7 Filed Sept. 17, 1947 Patented Nov. 20,1951 UNIT- D 1 STATE PAT iNTEnNAmCOMBUsTIoN'ENGiNEf 1. p GrardflohanLug't,'Amsterdam,Netherlandsyassignor to Werksp'oor N. -V.; a company ofthe Netherlands Application September 17, 1947, Serial Nb. 7.7;,542]

. I n vthel\let hferlan ds January 9, 1946 Section 1, Public Law 690;August 8, 1946 Patentexpires January 53,1966

. .Every internal combustion. engine comprises auxiliary'or controllingmeans which haveto be moved in correlation with. the movement .of. thepiston(s) By .way; of: example, valves,; pumps (e. g -compressorsiorfuel pumps) "and also indi- I cator'devices may be mentioned. Inatwo-cycle engine of the longitudinal. scavenging .or unifiow type such ameans may be, in particular the outletmeans in the cylindercover.,.. f iV Such-auxiliary and controlling means ,are usually drivenby meansof-acamshaft, or sometimes from the crosshead or. the crank shaft. From aconstructionalpoint of viewthe devices required for this purposearefcomplexandgespensive. According to the present invention,thejauxiliary and controlling means of .a cylinder which have to bemoved in correlation with. the vrnoyementof thepistonare driven by anelement that moves up and down in time with the piston in such a mannerthat this elementfand the piston pass: simultaneously through thedeadcentre; -a phase shifting mechanism being inserted; if necessary,between the auxiliary'or controlling means in question and the drivingelementl' Preferably the driving element is the piston mechanism of apiston pump, particularly of "a scavenging air-pump. e l The abovearrangement results in' theproduction-of simple, reliable and'relativelyinexpensive constructions. I I

When the driving element in question and the piston pass simultaneouslythroughthe dead centre, the movement of: the-drivin elementissymmetrical with respect to the dead centre of the I j. "13. can;(01.123540) mentwith respect to the driving. movement'has piston. Thispresentsithe advantagethat the movement .of the driving element withregard .to:-the movement of the piston isiindependent cfthe,direction,;vof -rotation ,of. the crank shaft,

and consequently is thejsamei for both forwardf' and reverse rotation.Such a movementahowever, cannot be used assuch forthe movement of theoutlet .valve of 1a. twpstroke engine having longitudinal scavenginfl0w.,;1 he anglepfrthe crank within which this valve {has to, open before the dead centreislarger than lthe angle within which it/ ha's .toclose beyond .;the dead centre. This means that themove ne nt of thevalve is not 'symmetrica-l with respect ,to the dead centre.

It does not seem diflicu lt toderive above mentioned symmetricalmovement of ,the

Tri

.-.-.Accordi ng to..the.invention, the mechanism connecting,- thedriving element to :the: auxiliary or controlling means driven by itcontainsato that effect at least :two elements which co-operate to givethe required movement and one of which at least is :multiplewith'function changing-parts or: is changeable in position, while adevice isprovided which causes the said" changing of function or ofpositioninthe driving 'element=periodically. .1 w Inthe accompanyingdrawing: Fig. 1 is asectionalview'of the cylinder ore two'cycleinternal-combustionengineof the uniflowor longitudinal type;"'-* f Fig.lais-asectionalviewof a two cyclein'ternal combustion 'engin'e showing"the cooperative relation of the driving meansjto'aiuel pump} asectiontaken onthe linejll l llfi in Fig; '5 is aside view of anothermbeq i entnf hi ani m; y I e v Big. 6 isa side view of athirdembodim'ent, and

' Fi Tie a side viewofa; fourth embodiment. In Fig. l a cylinder,joffbl?ter; a. cyl inderliner "'l is shown, which is provided with scavengingports 2, a cover being providedwith a number of 'outlet valves 3'. ThepisfiQn. 4, iswrat her short, as

is usual with'this typeioi engine, and connected by'a' c'onnectingrod 5toacranl; 6 ate crank vfshaft'l. I v ,4; A scavenging airpumpisfit ednext to the ens s l er end-con i t bf a Pum yl n erfi with a piston},as.low as possible..in order. to permit .of lateral inspection. andsideward dismou'nting of the piston.4'.'; .Thefendof the piston section:takenfon the line II -II in 3 rod I is on a cross head II which movesalong aguide I2.

Beneath the engine cylinder I and the pump cylinder 8 a lever I6 ispivoted upon the point I5. Its end is connected to the motor piston 4 bya connecting rod II, by which it is also driven. Further, the lever I6,in turn, drives the scavenging air pump through the medium of aconnecting rod I8 applied to the cross head II.

The movement of the pump piston 9 will be not only in time with themotor piston 4, but even in entire conformity with the movement of themotor piston, only with a smaller stroke. The coupling of these twopistons forms a pantograph system.

A piston rod 22 connected to the pump piston 9 passes through a stufiingbox in a cover 2I of the pump cylinder 8. A piston rod 22 forms thedriving element for the auxiliary and controlling means.

The end of the rod 22 is provided with a cam body 23, against which aroller 24 is pressed. This roller 24 is mounted at the end of aleversystem 25, to which rocking levers 26 are connected, which leverscontrol the valve rods 21 of the outlet valves 3. It will easily be seenthat the shape of the cam 23 is such that at the end of the downwardstroke of the motor piston 4 the outlet valves 3 open before the ports 2open and that the outlet valves 3 remain open till the cylinder has beenscavenged by air flowing through the ports 2 and the outlet valves 3.Adjustment can take place by varying the position of the cam 23 on therod 22.

When it is required that the points of opening and closing of the valvesor other elements are not symmetrical with respect to the dead centres,at phase-shifting mechanism must be applied in order to obtain theunsymmetrical movement required.

Furthermore the paper or registration drum 30 of the indicator mechanismis also driven from the rod 22, and a device for reversal and reductionof the movement is necessary. As such there is provided a shaft carryingcable drums 3I and 32 respectively of different diameters. on which thecables 33 and 34 respectively are wound in opposite direction. Theformer cable is attached to the indicator, the latter to the rod 22.

When shifted diagrams are required (showing a phase-difierence of 90with respect tothe engine), another device for transformation ofmovement is provided for that purpose (e. g. a crank mechanism withcranks at 90).

In the motor shown in the drawing, the starting valve device or itscontrol device, the supercharging device (for introducing combustion airunder pressure into the cylinder) and the fuel pump can be driven,controlled or regulated from the rod 22.

In Fig. let I have shown a fuel pump plunger a which is driven by a camb on the piston rod 22 of the scavenging pump piston 9. The supplyconduit for the fuel oil is indicated by reference character 0 and isconnected to the fuel pump cylinder over a suction valve (1. When thepump plunger a has been retracted the oil will circulate from the supplyconduit c to the pump cylinder and back to the return conduit e in orderto keep the oil flowing constantly. The fuel injector is indicated bythe reference character 1, and as a rule the injector f is not mountedon the corresponding motor cylinder I but on another cylinder of thesame engine. It would be possible to have the injector f mounted on itsown cylinder I but then a phase of shifting mechanism would be needed inorder to obtain a longer injection period after the motor piston 4 hasreached the outer dead center, which would complicate the design.

In Figs. 2, 3 and 4, a rod IIII forms the driving element. It may be,for example, the extended piston rod of a scavenging air pump driven bya balance from the cross head of an engine cylinder and consequentlyhaving a movement in the rhythm of the engine piston. The rod IOIcarries a cross head I02 moving along the guide I03. and the cross headI02 carries a roller I04.

The outlet valve to be controlled is driven by a. rod I05, which isfitted to a lever I06 pivoting about a fixed point IB'I. It will beunderstood that When the roller I04 moves up and down along acam-surface on the lever I06, this lever I06 pivots about its fixedpoint I0! and thus acts upon the rod I05. Care has to be taken, that themovement of the lever I06, when the roller I04 moves downward, isdifierent from the movement of the lever when the roller I04 movesupward. This can be effected by an arrangement in which different camson the lever I06 are in contact with the roller I04 when it moves upwardand when it moves downward.

For this purpose the lever I06 is provided with a cam unit I08comprising a set of cams I09 (three cams) and a set of cams III] (alsothree cams). The roller I04 consists of three coaxial discs of equalsize co-operating with either the cams I09 or the cams H0. The positionof the roller I04 is variable in axial direction in the cross head I02.When this roller I04 is in the position shown in Figs. 3 and 4, itco-operates with the cams I09, but when it shifts it co-operates withthe cams III). Thi shifting is effected with the aid of an arm rockinglever I I I, which strikes an abutment H2 when the rod I0] movesdownward. At the upper dead centre a shifting in the opposite directionhas to be effected, and this can be done in the same manner by a rockinglever H3 co-operating with an abutment H4.

The position shown in Fig. 2 corresponds with the beginning of theopening of the outlet valve of the two-stroke engine. When the axis ofthe roller comes into the position indicated by the dotted line H5, theengine piston is at its lower dead centre and the movement reverses, theroller I04 now following the cam H0, so that the outlet valve is againclosed when the axis of the roller is in the position indicated by thedotted line I I6.

The roller I04 is divided into separate discs (three, in the drawing) inorder that a small axial shift may suflice. In position H5 the discs arein contact with both the cams I09 and the cams I I0, so that shiftingcan take place without shock. During the shifting at the lower deadcentre an auxiliary roller (not shown) can be used in order to avoidcontact between the roller I04 and the cams I09 and H0, so that shiftingcan take place without friction.

Of course the positions of the roller I04 and the cam I08 can beinterchanged.

In the embodiment according to Fig. 5, as opposed to that of Figs. 2-4,the roller is immovably fitted in the cross head I02, but the cam isadjustable. For this purpose the lever I06 carries a single cam I20,which is adjustable with respect to the lever I 06, viz. by means of twolinks I2I and I22, pivoted at the points I23 and I24 respectively of thelever I06. The other extremities of the links I2Iand I22 are' pivoted'atthe points""I25 andIZB' respectively of thecam." "At the downward strokeof*the rod*II'-the roller I04 pressesthe cam I20 against the fixedabutmentsl2! and I28 'ofthe -lever- 106. The cam I20 i moreovermaintained in that position byatension spring I29, attached'to thejfreeend of the'link I22.- The position and the shape of the cam Ilfl-ainesuch that' th'e rod' I05 is acted upon at-fthe correct mo'ment: Inthe'drawing the position corresponding with the initial opening of theoutletvalve isshown. It is to be noted that the links IZI- 'and I22 -arenot'understress', the-whole force being taken up by the abutments I21 andI28.

After the roller I04 has passed'the nose of-the cam and is consequentlyapplied to the fixed *cam -I'I"9 'of the lever I06, the rodIOI'movesagain upward, and the' couple acting'on the cam I undertheinfluence of the pressure exerted'on =it by' the roller l04 is inverted,as-a resultof'which the cam' is moved upward intothe positionshownindott'ed linea i Consequently the roller I04 runs-upwards from the caml-l9 alongacam surface of a shape or is closedz 1 The dotted line II5mark the low'er dead centre. v In the embodiment of Fig.- 6-' the'roller l04 forms a part of the lever I05, whereas the cross head I 02is provided with the cam; The roller I04 '(which' may be multiple) ismounted in a yoke I pivoted at'a point I3I. A spring 132 maintains theshaft I33 of the roller I04 in contact with-a cam I34 on the lever I05.

When the-cross head-I02 moves downward, a I

cam; I35 touches the roller I04, as a result/of which the lever I06'is-r'noved. The position illustrated corresponds with the beginningof this movement (opening 'of the outlet valve) 1 The lever- I06 carriesanother roller I36 which isalso: controlled by the cam I 35. cam I35enters into contact with the roller I36, it loses contact with theroller I04, and when after having reached'the lower dead centre it againmoves upward, the roller I 04 is pushed away and broughttothe position I31 shown in dotted lines, so thatthe cam I35 i applied to the roller I36 only. This means that the lever I06 quickly swings back, the dottedline IIB marking the 'pos'ition at which theclosing of the outlet valvetakes place, and the positionof the cam within the path limited-by thedotted line I40 (beginning of the opening of the outlet valve) and thedotted line I4I (lower dead centre). The outlet valve (not shown) iscontrolled by a connecting rod I42. A lever I44 is fitted to this rodI42 at the pivot I43. The point I43 is conducted When this in i acircular path by means of a; link I45 pivoted at the fixed point I45;the circle of which coincides as much asflpossible with theevolutevline described'by the point 443 iwhen -the lever I44 rolls or isevolved on a curved fixedttrack I41". Theoth'er end'of-the'lever .Ie4(pivot I48) is connected'by means of a link I49=-to' a -pivot-I50at theextremity of the connectingnrod lfil moving upand down. 1=At the upperdead centres-ISIthis link occupies the position I4.9'eand the-pivot lc48is atthe 'position- I48". The curved evolvingr'track I4! is pivoted atone endx-upona fixed pbintl52, while it rests at the'other end upon atwo-sarm lever I53 pivoted at .the fixedz point1 I54: -At the lowerdeadtcentre the protruding"- pin I5 0 of. the rod IOI presses againsttheextremity 1550i the lever I 53,. as a sr'esult-of which-the latter:is put in the position shown inrdotted liness-andc-the guide I4 I; is"pressed downward, pivoting .upon the point -I 52, .into the position:shown in dotted lines against :the abutment I56: Consequently the point=-I 43 also drops; together: withthe pushing rod*I'42,l sothat in theupward stroke the closing ottheivalve comes earlier. Thetrack M Iis thenagain completely discharged and a springer-I51 causes the track I4Tand'the lever -I53-.to return totheir originalpositions. -1 Thisconstruction maybe variedrin manywa'ys. The track. I41 can be fixed :andthemoving parts maynbesplaced inthe lever I444: The' p0inttI'43 mayalso-be guidedin' aright liner insteaduof pivoting uponpo'int I46, Theabutment I58 may be provided with ia bufier-mechanismin orderto absorbthe shock at-thelower dead zcentre. :zflhe principle of this latterconstruction is that no cams and rollers are used-but instead ofthese a.lever I44 rolls or evolves on-a curvedtrack I41, theposition 1of-1thetrack I4'I being different in the upward and downward movement oftheconnectingrod-IBI. :2-

.- I i What Iclaim is:- f- 5': I 1; A two-stroker'internal--combustion--. engine of :the uni-directional flow type,. comprising a:power cylinder closed-at one end, a reciprocatingpiston within thepower cylinder, a lcranksshafizaconnecting rod and a crank 'operativelyconnecting the piston to the crank shaft, .said cylinder "being providedwith outlet means in its closed .endand withair inlet ports initswall-positioned rto-be uncovered by the piStOnrWhGIl it nearsits: innerdead :center, an air scavenger pump comprising a, pumpecylinder and-areciprocating pump piston within r the r pump cylinder, the pump"cylinder being located adjacent the power cylinder; and the pump pistonbeing provided with connecting rod mechanism aoperatively connectedtothemoving piston systemvof the power cylinder and, also to the outletmeans of I theflpower cylinder, the outlet passages of l the, air pump:being; in l .communication with .theairinlet ports inzthe wall of-thepower cylinder; z =1 1 2. A two-stroke internalcombustionenginemf theuni-directional. flow type, comprising .azpower cylinder closed at oneend, a reciproc'atingpiston within the power cylinder, a crankshaft, .aconnecting rod and a crank operatively connecting the piston to thecrank shaft,- said cylinder-being provided with outlet means in itsclosed end and with air inlet ports in its wall positioned to beuncovered by the pistonv when it nears its inner dead center, anindicator device mounted on the power cylinder, a pump comprising a pumpcylinder and a reciprocating pump piston moving within the pumpcylinder, the pump cylinder being located adjacent the power cylinder,the

7 pump piston being provided with connecting rod mechanism operativelyconnected to the moving piston system of the power cylinder and also tothe movable part of the indicator device which has to be driven in phasewith the power system.

3. A two-stroke internal combustion engine of the uni-directional flowtype, comprising a power cylinder closed at one end, a reciprocatingpiston within the power cylinder, a crank shaft, a connecting rod and acrank operatively connecting the piston to the crank shaft, saidcylinder being provided with outlet means in its closed end and with airinlet ports in its wall positioned to be uncovered by the piston when itnears its inner dead center, a fuel pump of the reciprocating typehaving its outlet communicating with a fuel injector, a second pumpcomprising a pump cylinder and a reciprocating pump piston moving withinthe said pump cylinder, the pump cylinder being located adjacent thepower cylinder, the pump piston being provided with connecting rodmechanism operatively connected to the moving piston system of the powercylinder and also to the reciprocating driving member of the fuel pump.

4. A two-stroke internal combustion engine of the uni-directional flowtype, comprising a power cylinder closed at one end, a reciprocatingpiston within the power cylinder, a crank shaft, a connecting rod and acrank operatively connecting the piston to the crank shaft, saidcylinder being provided with outlet means in its closed end and with airinlet ports in its wall positioned to be uncovered by the piston when itnears its inner dead center, a pump comprising a pump cylinder and areciprocating pump piston moving within the pump cylinder, the pumpcylinder being located adjacent the power cylinder, the pump pistonbeing provided with connecting rod mechanism operatively connected tothe moving piston system of the power cylinder and also to the outletmeans of the power cylinder and a phaseshifting device mounted betweenthe connecting rod mechanism of the pump and the outlet means of thepower cylinder.

5. A two-stroke internal combustion engine according to claim 4 whereinthe phase-shifting device comprises cooperating means to transmit thedriving movement from the said pump to the said outlet means, one ofsaid cooperating means having two different active parts which cooperateone at a time with the other of said means, said active parts beingperiodically shiftable for cooperation with the other of said means.

6. A two-stroke internal combustion engine according to claim 4 whereinsaid phase-shifting device comprises a roller and a cam unit consistingof two cams in staggered relation with respect to one another in adirection at right angles to the direction of the movement, said rollerand cam unit being adjustable in a transverse direction with respect toone another in such a manner that either one cam or the other cooperateswith the roller.

7. A two-stroke internal combustion engine according to claim 6, inwhich with respect to the roller and the cam unit only, the one locatedin the driving element connected to the said pump is adjustable in atransverse direction by cooperation with abutment mechanisms near theends of the stroke of the driving element.

8. A two-stroke internal combustion engine according to claim 4 whereinthe phase-shifting device comprises a roller and a cam, one of which ismovable in the plane of the relative movement from a working position toa, different working position, or from a working position to an inactiveposition, a second cam or roller being provided in the latter case, withwhich the roller or cam respectively, can cooperate when the firstmentioned cam or roller occupies its inactive position.

9. A two-stroke internal combustion engine according to claim 4 whereinthe phase-shifting device comprises a roller cooperating with a cam, thecam being movably fitted in its own plane by means of links, themovement being limited by an abutment in one working position in such amanner that when the relative movement of the roller reverses, or afterit has been discharged from the pressure of said roller, the cam turnsaway, thus forming or disengaging a different shape cam surface tocooperate with the roller.

10. A two-stroke internal combustion engine according to claim 4 whereinthe phase-shifting device comprises a roller cooperating with a cam, theroller being movably fitted in its own plane and supported in itsworking position by an abutment, a second stationary roller beingprovided to cooperate with the cam when the first mentioned rollerpasses to its inactive position under the influence of the cam reversingits relative movement.

11. A two stroke internal combustion engine according to claim 2 whereinthe pump is an air scavenger pump, the outlet passages of which are incommunication with the air inlet ports in the wall of the powercylinder.

12. A two stroke internal combustion engine according to claim 3 whereinthe second pump is an air scavenger pump, the outlet passages of whichare in communication with the inlet ports in the wall of the powercylinder.

13. A two stroke internal combustion engine according to claim 4 whereinthe pump is an air scavenger pump, the outlet passages of which are incommunication with the air inlet ports in the wall of the powercylinder.

GERARD J OHAN LUGT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Bernard Oct. 24, 1933

